/*
 *  Copyright 2012 GWT-Bootstrap
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package com.github.gwtbootstrap.client.ui;

import com.github.gwtbootstrap.client.ui.base.TextBoxBase;
import com.google.gwt.dom.client.Document;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.TextAreaElement;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.Widget;

/**
 * A TextArea for Bootstrap form.
 * 
 * @since 2.0.4.0
 * @author ohashi keisuke
 */
public class TextArea extends TextBoxBase {

	/**
	 * Creates a TextArea widget that wraps an existing &lt;textarea&gt;
	 * element.
	 * 
	 * This element must already be attached to the document. If the element is
	 * removed from the document, you must call
	 * {@link RootPanel#detachNow(Widget)}.
	 * 
	 * @param element
	 *            the element to be wrapped
	 */
	public static TextArea wrap(Element element) {
		// Assert that the element is attached.
		assert Document.get().getBody().isOrHasChild(element);

		TextArea textArea = new TextArea(element);

		// Mark it attached and remember it for cleanup.
		textArea.onAttach();
		RootPanel.detachOnWindowClose(textArea);

		return textArea;
	}

	/**
	 * Creates an empty text area.
	 */
	public TextArea() {
		super(Document.get().createTextAreaElement());
		setStyleName("gwt-TextArea");
	}

	/**
	 * This constructor may be used by subclasses to explicitly use an existing
	 * element. This element must be a &lt;textarea&gt; element.
	 * 
	 * @param element
	 *            the element to be used
	 */
	protected TextArea(Element element) {
		super(element.<Element> cast());
		TextAreaElement.as(element);
	}

	/**
	 * Gets the requested width of the text box (this is not an exact value, as
	 * not all characters are created equal).
	 * 
	 * @return the requested width, in characters
	 */
	public int getCharacterWidth() {
		return getTextAreaElement().getCols();
	}

	@Override
	public int getCursorPos() {
		return getImpl().getTextAreaCursorPos(getElement());
	}

	@Override
	public int getSelectionLength() {
		return getImpl().getTextAreaSelectionLength(getElement());
	}

	/**
	 * Gets the number of text lines that are visible.
	 * 
	 * @return the number of visible lines
	 */
	public int getVisibleLines() {
		return getTextAreaElement().getRows();
	}

	/**
	 * Sets the requested width of the text box (this is not an exact value, as
	 * not all characters are created equal).
	 * 
	 * @param width
	 *            the requested width, in characters
	 */
	public void setCharacterWidth(int width) {
		getTextAreaElement().setCols(width);
	}

	/**
	 * Sets the number of text lines that are visible.
	 * 
	 * @param lines
	 *            the number of visible lines
	 */
	public void setVisibleLines(int lines) {
		getTextAreaElement().setRows(lines);
	}

	private TextAreaElement getTextAreaElement() {
		return getElement().cast();
	}

}
